The production of polyurethanes with the aid of various kinds of catalysts is known. When polyurethane composite materials and fabricated polyurethane products are produced, for example, from polyurethane foams and covering materials such as colored polyvinyl chloride or ABS foils or textile covering layers of cotton or leather, it has frequently been found that the catalysts damage the covering materials due to diffusion.
In back foamed foils based on PVC and ABS, marked color changes occur in the covering and sheathing materials due to separation of the activators so that even foils which are originally light in color become very dark or even black.
U.S. Pat. No. 3,622,542 describes the use of N,N'-tetramethyl-2-hydroxy-1,3-diamino-propane as a catalyst for the production of polyurethane foams.
The function of the present invention is to discover catalysts which
1. show no tendency to produce diffusion effects and therefore prevent PA1 2. direct contact discoloration in covering materials as well as PA1 3. indirect changes in color and constitution of adjacent materials due to separation of catalyst, PA1 R.sup.5, R.sup.6, R.sup.7 and R.sup.8 may be identical or different and represent a C.sub.1 -C.sub.6 alkyl group or may combine to form a C.sub.2 -C.sub.6 alkylene group which may contain hetero atoms such as O or NR (R=C.sub.1 -C.sub.4 alkyl), and PA1 n and m may be identical or different and represent integers from 1 to 6. PA1 n=2-4, preferably 2 or 3, and PA1 Q represents an aliphatic hydrocarbon group having 2 to 18, preferably 6-10 carbon atoms; a cycloaliphatic hydrocarbon group having 4-15, preferably 5-10 carbon atoms; an aromatic hydrocarbon group having 6-15, preferably 6-13 carbon atoms; or an araliphatic hydrocarbon group having 8-15, preferably 8-13 carbon atoms; suitable polyisocyanates are also described in German Offenlegungsschrift No. 2,832,253, pages 10-11. PA1 (a) water and/or readily volatile organic substances as blowing agents, PA1 (b) catalysts of a known type used in quantities of up to 50% by weight, based on the quantity of the catalysts which are to be used according to the invention, PA1 (c) surface active additives such as emulsifiers and foam stabilizers, PA1 (d) reaction retarders (e.g. compounds which are acidic in reaction such as hydrochloric acid or organic acid halides), known cell regulators (such as paraffins or fatty alcohols or dimethyl polysiloxanes), pigments or dyes, flame retarders (e.g. tris-chloroethyl phosphate and tricresyl phosphate), stabilizers against ageing and weathering, plasticizers and fungistatic and bacteriostatic substances, as well as fillers (such as barium sulphate, kieselguhr, carbon black or whiting).
even when polyurethane composite materials and fabricated polyurethane products are subjected to heat.
This problem is solved by means of the catalysts used according to the invention.